The Therapeutic Effect Of Calcitonin On Lumbar Intervertebral Disc Degeneration In Guinea Pigs

Objectives Hartley guinea pig is a widely used spontaneous model of disc degeneration,and through this experiment, we can understand the classical treatment of osteoporosisdrugs calcitonin (Calcitonin, CT) whether can prevent spontaneous disc degeneration inguinea pigs.Methods Thirty-two1-month-old guinea pigs were divided into four groups: baselinegroup (G1),8guinea pigs sacrificed at1months of age with the starting time of theexperiment; the control group (G2),8guinea pigs were treated by normal feeding andsacrificed at3months of age;8guinea pigs were treated by normal saline from3months of age, and sacrificed at9(G3) months of age; the other8received CT(16IU/Kg/2d) from3months of age, and were sacrificed at9(G4) months. Ahistomorphometric study was based on the Van Gieson and graded by Histological scoresof lumbar intervertebral disc. lumbar spine bone mineral density measured by bonedensity measuring instrument; Immunohistochemistry analyses of Col-Ⅱ, MMP-1andMMP-3in the annulus.Results1Bone density test results show that: G2group bone mineral density wassignificantly higher than G1group (P <0.05); G4bone mineral density was significantlyhigher than G3group (P <0.05).2Histological staining: Lumbar disc histologicalscores showed: G3group score were significantly higher than the results of G1and G2group (P <0.05); G4group score significantly lower than the results of G3group (P <0.05), and higher than the G1and G2group (P <0.05).3Immunohistochemical stainingresults: G3group of MMP-1and MMP-3expression were significantly higher than theresults of G1and G2group (P <0.05); G4group of MMP-3and MMP-1expression wassignificantly lower than G3group (P <0.05); G3group of Col-Ⅱexpression group weresignificantly lower than in G1and G2group (P <0.05), G4group of Col-Ⅱexpressionwas significantly higher than the G3group (P <0.05).Conclusions19-month-old Hartley guinea pigs apprared significantly discdegeneration, Hartley guinea pig as a model of spontaneous disc degeneration isscientific and reasonable.2Salmon calcitonin (16IU/kg/48h) can significantly reduce the expression of MMP-1and MMP-3, increased expression of collagen typeⅡin theHartley guinea pig lumbar intervertebral disc cells. CT could be used for conservativetreatment of disc degeneration.